Radio communication systems which support communication among several users operating in wireless environment over radio frequencies are known. The frequencies used by these systems are a subset of the radio frequency spectrum which are organized into one or more radio communication channels, such as frequency channels. In such a system, for example, a communication link may be established between groups of communication devices within the radio system. The communication link is established over one or more frequency channels for the duration of the communication. Generally, the frequency spectrum available for a given radio system is a limited communication resource, and several users may be competing for this resource. Thus, a radio communication system typically employs a frequency management methodology in order to maximize the efficient use of the available frequencies, and to minimize interference among users. This approach is essential where multiple communication links must be established over shared communication channels.
Many frequency sharing methodologies are known in the art. Examples include, channel hopping, direct sequence spread spectrum, time division multiplex, and other similar schemes. Most prior art frequency sharing methods employ an infrastructure to manage the operational aspects of a radio communication system. An infrastructure typically includes a base station, or some other type of controller, which manages frequency assignments, user access, collision detection and resolution, and other operational aspects of a radio system. These controllers tend to represent a significant cost in the establishment of a radio communication system.
Low cost radio communication systems are becoming an increasingly important segment of the wireless communication market. These low cost systems must also successfully manage frequency usage among users in order to maximize efficiency and throughput. Some low cost systems involving self-organizing units employ frequency management methodologies which do not require the use of a central controller. However, without a central controller, frequency management issues, such as collision detection and resolution, become more difficult. Therefore, it is desirable to have frequency sharing management methodologies which are suitable for low cost radio communication systems.